Device for removal of tar and other deleterious substances from tobacco smoke



Oct. 4, 1960 H. A. LEBERT 2,954,780

. DEVICE FOR REMOVAL OF TAR AND OTHER DELETERIOUS SUBSTANCES FRQMTOBACCO, SMOKE Filed Dec. 23, 1957 H, x IIIIIIIIllIIIIIlIIII/lllllV 1infa Patented Oct. 4, 1960 DEVICE FOR REMOVAL OF TAR AND OTHERgE-LETERIOUS SUBSTANCES FROM TOBACCO MOKE Herbert A. Lebert,MillbraegCalifi, assignor to Mac- Farland, Aveyard & Company, Chicago,111., a corporation of Delaware FiledDec. 23, 1957, Ser. No. 704,422 2Claims. (Cl. 131-187) This invention relates to the removal of tar andother deleterious substances from tobacco smoke and particularly to anorifice and impingement barrier combination for the removal of tars,resins, and other harmful substances in the smoke. In the followingdescription, such harmful substances will be referred to for convenienceas tars.

In the past, many devices have been proposed for the treatment oftobacco smoke and for the elimination of portions or fractions ofcomponent parts of the smoke therefrom. The removal of tars has posed aserious problem because of their known harmful effects to health.Screens and orifice-equipped disks have been proposed, the effectiveopening for the flow of smoke being quite minute, but while some tar isremoved in the operation of such devices, a satisfying flow of smoke isnot obtained. Furthermore, a sufficient proportion of the tars are notremoved.

The present structure or tar filter device fundamentally differs fromprevious types of tar filter devices by obtaining tar separation bymeans of providing a structure adapted to cause tar separation byimpingement of high velocity tar ladened smoke against an impingementbarrier. Tests tend to indicate the present new technique is far moreeffective than any previously known tar filtering device in effectivelyremoving tars and especially the more dangerous high temperature tarsfrom tobacco smoke while at the same time enabling the smoker to obtaina pleasurable smoke without a hard draw.

The results of research by independent experts in this field tend toindicate that the tars extracted from the lower temperature-burningranges (560 to 720 C.) produce few or no cancers. The number of cancersincreased sharply through the use of tar taken from tobacco burning fromthe higher temperature ranges (720 to 880 C.). Tests have also shownthat a cigarette burns between 800 to 880 C. so that the more dangeroushigh temperature tars are presently being inhaled by the cigarettesmokers. (See Time magazine, April 22, 1957, page 50.)

Early experiments indicate that where the velocity eX- pansion coolingprinciple is used to obtain tar separation, a relatively low percentageof the high temperature tars are separated out of the smoke as opposedto the use of the instant relationship involving high velocity tobaccosmoke impingement without expansion wherein a relatively high percentageof high temperature tars are separated.

In the application of this new technique, manufacturing advantages arepresent since structures of this type are far more compact than thoseusing the velocity-expansion principle where a relatively large chamberis required for condensing the smoke. 7

It has been found that there is a practical dimensional range withregard to the size of the orifice and its distance from the barrier.

.If the orifice is too small the smoker is inconvenienced through hisdifiiculty in drawing the smoke through the device, and if the orificeis too large, the velocity of the smoke passing through the device isreduced in a manner whereby the percentage of tar separation ismaterially reduced. If the gap between the orifice and the barrier istoo great or too small the A, percentage of tar separation or the rateof tar flow is adversely effected. In this respect, the impingementbarrier is almost in contact with the orifice with there being justenough clearance to allow the formed relatively viscous tar to flow outof the path of the tar subsequently 3 formed. There is no expansionspace or condensing surface as in the above patents required here fortar separation from the smoke.

By using an orifice with a .028" to .030 diameter and a distance betweenthe impingement barrier and the orifice of to 1 the best results areobtainable. In other words, by constructing a device incorporating theabove dimensional range, the smoker may have a more pleasurable easydraw smoke with the high percentage removal of the tars including themore dangerous high temperature tar. Early tests of structures utilizingthis principle tend to indicate that at least 40% of the tars may beremoved. This 40% represents almost of the high temperature formed tarswhile the low temperature aromatic fractions of smoke are passed on tothe smoker.

Accordingly, a very important object of the present invention is toprovide means for the tar removal fromtobacco smoke through the use ofan impingement barrier employed at a spaced and effective distance froma Venturi orifice or a small orifice which causes the smoke to flow at asufiicient velocity to cause separation of the tar as the smoke strikesthe impingement barrier.

Another object of this invention is to provide a multipart cigarettestructure having novel means for separating tars including a highpercentage of high temperature tars from tobacco smoke While at the sametime allowing the smoke to be drawn through the cigarette holder withoutgreat difficulty enabling a smoker to obtain a pleasurable smoke withoutthe danger attendant with the drawing of the high temperature tars intothe body and lungs of the smoker.

Another object of this invention is to provide a multipart cigaretteholder structure which is easy to clean by readily separating the parts,and which structure may be manufactured on a large production basis atan economical cost.

A further object of this invention is to provide a thermoplastic holderhaving new and improved structure for separating tars from tobacco smokewhich insert is adapted for use in a tobacco burning smoking structure.

Yet another object of the present invention is to provide a highlycompact structure for separating the tar from tobacco smoke.

Other objects and features of the present invention will more fullybecome apparent in View of the following detailed description taken inconjunction with the accompanying drawings illustrating therein a singleembodiment, and in which:

Figure 1 is a top plan view of a multi-part cigarette holder structurecarrying a cigarette and which holder structure has tar separationstructure according to the principles of the present invention.

Figure 2 is an enlarged exploded view of the multi part cigarette holderstructure shown in Figure 1;

Figure 3 is an enlarged fragmentary cross-sectional view takensubstantially along the line IIIIII on Fig ure 1 looking into thedirection indicated by the arrows;

Figure 4 is an enlarged fragmentary cross-sectional view of a portion ofthe structure shown in Figure 3;

and

suitable materials although I have found that excellent, results may beattained through the manufacture. of'the,

mouthpiece 12 from a suitable plastic, such as thermoplastic, a suitablecomposition, or any suitable material.

The outer sleeve or tube 13 may be manufactured. from,-

metal or plastics, or from any suitable material.

The mouthpiece 12 has an. enlarged or transversely elongated downstreamend 14 and a reduced diameteredupstream end portion 15 with an axiallyvor longitudinally upstream facing shoulder 16 disposed at the junctionof the reduced end portion 15 with the full diameter body portion of themouthpiece 12. The reduced end, portion 15 most suitably has a circularperipheral surface 15a having a diameter corresponding to the outsidediameter of peripheral surface 11a of the cigarette. Thetubular sleeve13 most suitably has an internal circular surface 13a having a diametervery slightly at variance with the diameters of the peripheral surfaces11a and 15a of thev cigarette 11 and the reduced end portion 15. Thuswhen. the components are assembled, the sleeve has an. annular shoulder13b abutted against the annular shonld'er'16 of the mouthpiece and theinternal surface 13a is frictionally engaged with the peripheral surface15a of the reduced end 15. The sleeve 13 has a free cigarette-receivingsocket end portion projecting beyond a blunt forwardly facing stop end15b of the mouthpiece and is flared at 130 at the tip end of the socketto aid in telescoping the butt end of the cigarette 11 inside of thesleeve socket in frictional engagement therewith and with the cigaretteabutted against the circular longitudinally forwardly facing shoulder15b.

The mouthpiece 12 includes a main longitudinally extending passageway12a which extends into and internally of the reduced end 15 whereuponthe main passageway is linked to a radial passageway 15c.

Extended along the length of the reduced end in longitudinally oraxially spaced relation is a series of annular or circular grooves orpassageways 15d which are separated by annular lands or partitions 152and linked together by single reduced cross-sectional flow arealongitudinal or axial grooves or passages 8 respectively extendingthrough the peripheries of the partitions 15a and which passages. 18 arealternated in approximately 180 relation to one another. The grooves15d. and 18 are both semi-circular in cross section and openingoutwardly from the periphery of the mouthpiece reduced diameter portion15 for easy cleaning.

Disposed radially of the area of the shoulder 15b. the reduced endportion 15 is formed with a rabbet groove prow'ding an annular steppedshoulder area 15 f defining a smoke collection recessarea about the stopshoulder 15b. The stepped groove 15 thecigarette 11 and the sleevesurface 13a cooperate together to define a smoke collection chamber 1'7.The reduced flow area passages. 18 define discharge orifices ofpredetermined cross-sectional fiow'area or diameter. The annular grooves15d have wallareas longitudinally or axially opposite the orifices 18defining impingement barriers 19 so that the smoke mayv passthroughthe-orifices 18 at highvelocitytoimpinge tar T from the smoke upon thecollision of the smokeagainst. the barrier 19 in each instance.

As heretofore stated, the problem presented has beenone. of. providing.sufficient. smoke flow to satisfy the smoker, while at the same timeremoving the deleterious tars,,etc.. In. the structure of the presentinvention, this result is achieved by employing an impingement barrierin combinationwith an orifice which greatly increases the velocityof'the smoke stream so-that when the stream strikes the barrier, the taris lodged and collected upon the surface of the barrier 19 and in thechamber respectively providing by each of the grooves 15d and theresulting purified smoke alters its course through the passageway 15cand passes on to the smoker through the mouthpiece. While there will bevariations in the size of the orifice, and in the spacing of the barrierfrom the outlet of the orifice, depending upon' the character of thesmoke, the density of the cigarette mass, etc., I find that in generalefiective results are obtained where the orifice diameter isfrom .025"to .038 (square inch area of .0005 to .001). Very satisfactory resultshave been obtained 1 where the orifice diameter is .028 to .032 (.0006to .0008

square inch)". As a preferred example, I have employed effectively anorifice havinga diameter of 0.030 (.0007 square inch), which givesexcellent tar removal and ease of drawing. I

The critical orifice size is correlated. with the impingement barrierwhich is located as close as possible to the orifice or Venturi outletconsistent with the free flowing of the collected tars; e.g., withoutimpairing the flowing of the tar away from the point of impingement. Inpractice, I have found that a satisfactory range is a distance of 3 toof an inch, or about .03 to .187 of an inch. A still more satisfactoryrange lies between to of an inch. A preferred distance is .030 of aninch. In the specific example referred to, the barrier is spaced fromthe orifice outlet by of an inch (.030 of an inch), or approximately theorifice diameter.

The operation resulting from the structure shown here in is in contrastto the operation of cooling devices heretofore employed with cigarettes.Such cooling devices bring about a peripheral cooling of the smoke butallow substantial core portions of the tars to pass on to the smoker. Inmy structure, the entire cross section of the smoke strearn is subjectto the action of the impingement barrier so that the tars and otherharmful particles are removed by the foregoing high velocity impingementaction upon the barrier.

The barrier is presently illustrated as a solid barrier. The slightspacing between the outlet of the orifice and the barrier enables thesmoke stream to reach the barrier with substantially undiminished speed,while at the same time enabling the purified smoke to change directionwhereas tar fractions, by reason of their high inertia, can not changedirection and therefore deposit on the first surface contacted.

The passage or orifice is effective in greatly increasingthe velocity ofthe smoke so that it is substantially in excess of feet per second. Ofcourse, the velocity will vary considerably with different smokers andwith cigarettes of varying degrees of density. By spacing the barrierclose to the outlet of the orifice, the attained high velocity iseffective in lodging the tar fractions directly upon the barrier wallwhere an impervious barrier is employed, and further, such high velocityis effective, in the case of the solid barrier wall, in moving theviscous tar along the barrier face to an unobstructing position in thesump or reservoir space. The space between orifice outlet andimpingement barrier may be from 0.01 to 0.187". In the preferredstructure, the spacing is about 0.30.

In operation, upon the smoker applying a suction force on the enlargedend 14, smoke is drawn through the ignited cigarette into the smokecollection chamber 17 and then into thefirst orifice passage 18 in theseries. A high velocity smoke stream is formed 'as the smoke is drawnthrough the orifice 18, and the smoke stream is impinged against thebarrier 19 leaving the tars T. The smoke stream is deflected in oppositedirections away from the barrier 19 dividing the stream into sub-streamswhich are flowed in semi-circles and are merged at the next' orifice 18in the series which is circumferentially spaced from thefirst-in-the-series orifice 18 approximately on the opposite side of thereduced end' portion 15 so that tars collected at the barrier will notinterfere with the passage of the smoke through the second reducedorifice passageway 18. The smoke stream then passes through the secondorifice 18 and is directed at high velocity against the barrier 19confronting it and more tars are separated from the smoke with thestream again being divided into sub-streams and then collected andpassed through a third reduced orifice passageway 18 against a thirdbarrier 19 downstream therefrom. The smoke after striking the lastbarrier, and any suitable number of barriers may be employed, is thendeflected into the radial passage 15c and out through the main passage12a into the smokers mouth.

The passageways 15d and 18 are preferably semicircular and disposed atthe periphery of the reduced end portion 15 since upon pulling thesleeve and removing it from the reduced end, a cloth may be used to wipethe tar out of the grooves. The grooves are separated by the dividinglands 15e whose peripheral portions of the surface 15a form asubstantially air tight fit with the sleeve 13.

It will be understood that modifications and variations may be effectedwithout departing from the scope of the novel concepts of the presentinvention.

I claim as my invention:

.1. In a device for removal of tar and other deleterious substances fromtobacco smoke, a mouthpiece having a forward end portion, a sleeveremovably engaging encompassingly about said end portion and projectingforwardly therefrom and providing a socket receptive therein of the buttend portion of a smokable article, the forward article opposing end ofsaid end portion having a smoke collecting recess therein, the peripheryof said end portion having a plurality of annular grooves therein spacedfrom one another by a partition land respectively therebetween, a singlelongitudinally extending peripheral orifice groove in said end portionconnecting said collection recess with one of said annular grooves whichis nearest said end and a single longitudinal orifice groove in theperiphery of the land partition separating said one annular groove fromthe next and adjacent annular groove thereto and ofisetcircumferentially a substantial distance relative to the first mentionedorifice groove, said mouthpiece having a rearwardly opening passagewaytherein extending forwardly short of said forward end and communicatingwith said next adjacent annular groove, each of said orifice grooveshaving an orifice cross-sectional flow area of .0005 to .001 square inchwhereby to effect acceleration of smoke downstream therefrom at avelocity in excess of 100 feet per second and the respective annulargrooves into which the orifice grooves discharge presenting impingementbarriers confronting the downstream ends of the orifice grooves at adistance of .01 to .187 inch so that smoke issuing from each of theorifice grooves successively will impinge the respective barrier and dposit tars t ere n and move laterally in the respective annular grooveto continue downstream until the smoke passes out through saidpassageway, said sleeve providing a circumferential closure for all ofsaid grooves and maintaining said recess and said annular grooves insubstantially airtight separation so that communication therebetween islimited to said orifice grooves, said annular grooves and said orificegrooves being of smoothly rounded cross-section to facilitate cleaningthereof when said sleeve is removed from said end portion to expose thegrooves.

2. In a device for removal of tar and other deleterious substances fromtobacco smoke, an elongated mouthpiece having a generally cylindricalforward end portion, a sleeve removably encompassingly engaging said endportion and projecting therebeyond and providing a socket receptive of asmokable article therein, said end portion having a forward endsmoke-collecting recess therein, an annular groove in the periphery ofsaid end portion adjacent to said forward end but spaced from and closed011 from said recess by an intervening portion of said end portion andcircumferentially closed by said sleeve, a single longitudinalperipheral orifice groove in said intervening end portion connectingsaid recess and said annular groove and providing a smoke streamaccelerating orifice of a size of about .0005 to .001 square inchcross-sectional flow area, said groove providing an impingement barrierconfronting said orifice in a spaced relation of about .01 to .187 inch,the mouthpiece having a rearwardly opening longitudinal smoke passagewaytherein extending short of said forward end, the forward end portion ofsaid passageway communicating with said groove at a point ofisetperipherally from said orifice groove whereby smoke issuing at highspeed from said orifice impinges said barrier and then travels laterallyin said annular groove and passes on into said passageway, said annulargroove and said orifice groove being of rounded cross-section for easein cleaning when the sleeve is removed from said end portion.

References Cited in the file of this patent UNITED STATES PATENTS256,033 Naughten Apr. 4, 1882 708,404 Remore Sept. 2, 1902 925,381Regenold June 15, 1909 2,024,865 McArdle Dec. 17, 1935 2,202,288 HeronMay 28, 1940 2,385,651 Ricketts Sept. '25, 1945 2,511,898 Brothers June20, 1950 2,764,513 Brothers Sept. 25, 1956 FOREIGN PATENTS 146 GreatBritain 1880 155,189 Great Britain Dec. 16, 1920 341,552 France June 13,1904 760,772 Great Britain Nov. 7, 1956

